This is a continuation application of U.S. Ser. No. 10/684,375, filed Oct. 15, 2003, now U.S. Pat. No. 7,033,550.
The present invention relates to a catalytic exhaust gas decomposition apparatus and exhaust gas decomposition method for decomposing exhaust gases using a catalyst. The present invention relates also to an exhaust gas decomposition apparatus for decomposing PFC (perfluorocompounds).
As an example of an exhaust gas decomposition apparatus for decomposing exhaust gases using a catalyst, it is known that a spiral flow of an exhaust gas and a reactant gas is formed, allowed to pass through a baffle pipe for rectification, and is then introduced into a catalytic reactor (for example, see Japanese Patent Laid-open No. 7-185259 (claim 1, FIGS. 1 and 2)).
Japanese Patent Laid-open No. 7-185259 discloses an exhaust gas decomposition apparatus, in which a silane exhaust gas discharged out of a semiconductor processing reactor is diluted with a nitrogen gas, reacted with air, and led to a particle filter and introduced into a catalytic reactor. This exhaust gas decomposition apparatus is provided with a spiral flow generator that forms a spiral flow of the silane exhaust gas and air, a spiral flow reactor, and a baffle pipe. The apparatus is further provided in a later stage thereof with the particle filter and the catalytic reactor.
In catalytic exhaust gas decomposition, it is desirable that exhaust gases be introduced to a catalyst bed with a velocity distribution as uniform as possible.
The aforementioned prior art is intended to extend the service life of the particle filter and catalytic reactor, not concerned with a means of making the velocity distribution of exhaust gases as uniform as possible.